Spatial resolution of domain copying in a magnetic domain expansion readout disk

In a magnetic amplifying magnetooptical system (MAMMOS) disk, the copying p rocess of a magnetic domain from the recording layer into the readout layer is investigated by using a laser spot diameter of 0.66 mum. Interference b etween neighboring bits occurs when the spatial resolution of the copy proc ess Is larger than half the domain size. It is observed that a reduction of the readout power from 2.3 to 2.0 mW corresponds to a decrease of the copy window from 0.5 to 0.06 mum. As a result, at 2.0 mW packed magnetic domain s with a width of only 0.11 mum have been resolved without interference by using domain expansion.